摘要
以纳米Si和碳纳米管(CNTs)为原料,通过简单喷雾干燥方法制备了石榴状结构的Si/CNTs复合负极材料。通过透射电子显微镜可以观察到,CNTs在石榴状复合材料中起到支撑骨架的作用,其中15 wt.%CNTs含量的复合材料具有最佳储锂性能。在200 mA/g的电流密度下循环100圈后,可逆比容量还有1063.2 mAh/g;在500 mA/g的电流密度下进行长循环测试,450圈之后的可逆比容量为710.3 mAh/g。Si/CNTs复合材料循环性能的提升,主要来自合理构筑的石榴状结构,CNTs在其中作为机械骨架可以减缓体积变化,作为导电网络可以提高整体材料导电性,降低电化学阻抗,有利于比容量的发挥。此外,石榴状结构中存在的孔隙也有利于维持电极结构稳定性。
Pomegranate-like structure Si/CNTs composite was prepared through spray drying process with Si nanoparticles and CNTs as raw material.In TEM images,CNTs were served as the support skeleton and Si/CNTs with 15 wt.%CNTs content delivers the best lithium storage performance.After 100 cycles at a current density of 200 mA/g,the reversible specific capacity is 1063.2 mAh/g.And the long-cycle test is performed under 500 mA/g,and the reversible capacity is 710.3 mAh/g after 450 cycles.The improvement of cycling stability mainly comes from the properly constructed pomegranate-like structure.In the unique structure,CNTs as a mechanical skeleton can accommodate the volume change.As the conductive network,it can improve the conductivity of the overall material and reduce the electrochemical impedance,which is more conducive to the delivering of capacity.Additionally,the pores in the composite are also beneficial to maintaining the structural stability.
作者
李建斌
任玉荣
彭工厂
贾树勇
袁红东
吴小珍
LI Jianbin;REN Yurong;PENG Gongchang;JIA Shuyong;YUAN Hongdong;WU Xiaozhen(School of Materials Science and Engineering, Changzhou University, Changzhou 213164, China;Jiangsu Province Engineering Research Center of Intelligent Manufacturing Technology for the New Energy Vehicle Power Battery, Changzhou 213164, China;Chengdu Organic Chemical Co., Ltd., Chinese Academy of Science, Chengdu 610041, China;Changzhou Baili Lithium Battery Smart Factory Co., Ltd., Changzhou 213022, China;Jiangsu BTR New Material Technology Co., Ltd., Changzhou 213251, China)
出处
《合成化学》
CAS
2022年第6期434-442,共9页
Chinese Journal of Synthetic Chemistry
基金
锂离子电池高体积能量密度硅/轻度剥离石墨负极材料的开发制备(CQ20210100)
压电效应调控SiOx@C复合材料锂离子输运行为研究(22078029)
喷雾干燥法制备硅/碳纳米管复合材料及储锂机理研究(ZMF20020427)。
关键词
硅
碳纳米管
负极材料
石榴状结构
喷雾干燥
制备
silicon
carbon nanotube
anode material
pomegranate-like structure
spray drying
preparation
